Fix Paho client cleanup after failed startup

[nkokitkar]

Force-close internally owned MQTT v3 and v5 clients after startup or shutdown failures while preserving shared-client ownership. Keep the primary lifecycle exception and suppress any close failure.

Description

Target

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Tracking

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• I have run mvn clean install -DskipTests locally from root folder and I have committed all auto-generated changes.

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[davsclaus]

Claude Code on behalf of davsclaus

Thanks for the contribution — the client leak on startup failure is a real bug and the fix pattern (try-catch-finally with addSuppressed) is well done. Good test coverage too.

Findings

1. Missing JIRA ticket (Medium)

Per project conventions, bug fixes should have a JIRA issue filed. This is a non-trivial fix across 6 files — please create a JIRA ticket and reference it in the PR title/commits (e.g. CAMEL-XXXXX: Fix Paho client cleanup after failed startup).

2. Producer classes have the same bug (Medium)

PahoProducer and PahoMqtt5Producer have the identical lifecycle leak — if client.connect() throws in doStart(), the MqttClient instance leaks its thread pool and file-based persistence. Was the scope intentionally limited to consumers? If so, please file a follow-up JIRA to track the producer fix.

3. catchThrowableOfType parameter order (Low)

The catchThrowableOfType(callable, type) two-argument overload was deprecated in AssertJ 3.22+ in favor of catchThrowableOfType(type, callable) (swapped parameter order). Consider using the non-deprecated form or assertThatThrownBy(...) instead.

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This review was generated by an AI agent and may contain inaccuracies. Please verify all suggestions before applying.

[davsclaus]

The catchThrowableOfType(callable, type) overload was deprecated in AssertJ 3.22+. Consider using the swapped parameter order:

Suggested change

	MqttException thrown = catchThrowableOfType(MqttException.class, consumer::doStart);

This applies to the other catchThrowableOfType calls in this file and in PahoMqtt5ConsumerLifecycleTest as well.